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Maximum values are from Table A-2, USEPA (2003). MRLs are from the ATSDR internet site (http://www.atsdr.cdc.gov/mrls.html). Chronic oral MRLs are shown unless noted with an A (acute) or I (intermediate). Chronic oral RfDs are from the USEPA Integrated Risk Information System (IRIS) internet site (http://www.epa.gov/iris/ ). There are no FDA action levels for these metals in fish.

Chromium was assumed to be 100% trivalent (Cr III) because available literature indicates this is the form most likely to be present in fish. For thallium, the RfDs for thallium chloride and thallium sulfate are shown. For vanadium, the RfD for vanadium pentoxide is shown.

Screening exposure doses for adults were calculated using the maximum metal concentration reported, an ingestion rate of 0.540 kg/day (traditional subsistence fish consumer), an annual exposure factor of 1 (365 days per year), an absorption factor of 1 (100%), and a body weight of 70 kg. Bioavailability was assumed to be 100%. In most cases, the maximum estimated exposure dose did not surpass the applicable MRL or RfD. and were not given further consideration in this consultation. Estimated adult exposure doses for Ni and Se were in the same concentration range, but slightly (1.2-1.3 times) greater than the respective MRL. Repeating screening exposure dose calculations for nickel and selenium using an ingestion rate of 0.170 kg/day and a body weight of 35 kg (for children) indicated that conservative exposure dose estimates for children were below the MRL or the RfD.

USEPA's IRIS web site lists the cancer classification as unknown or D (unclassifiable) for these metals.

USEPA has developed a screening level of 1.5 mg/kg for selenium (USEPA 2001). For fish with selenium levels 1.5 mg/kg, the monthly consumption limit is unrestricted (meaning more than 16 eight-oz. meals per month). The monthly consumption limit decreases to 12 meals/month when selenium levels are between 1.5 and 2.9 mg/kg. Selenium values in Lake Coeur d'Alene fish samples were below, or within, the range of those found in the upper Blackfoot River watershed where no fish consumption restriction exists (IDOH 2003).

ATSDR has established a provisional acute oral minimal risk level (MRL) for arsenic at 0.005 mg/kg/day. The acuteLOAEL is 0.05 mg/kg/day. This dose is associated with edema of the face, and gastrointestinal and upper respiratorysymptoms, skin lesions and hepatic dysfunction, abnormal electrocardiograms, and ocular lesions. No intermediateexposure duration oral MRLs have been established. The chronic exposure duration oral MRL is 0.0003 mg/kg/day.The human chronic no-observed-adverse-effect-level (NOAEL) is 0.0008 mg/kg/day.

EPA classifies arsenic as a Class A known human carcinogen by the oral and inhalation routes. Epidemiologicstudies of people exposed to arsenic in Taiwan indicate that exposure to arsenic is associated with skin cancer. Basedon that and other studies, USEPA considers arsenic to be a human carcinogen. USEPA has calculated a cancer unitrisk factor, 1.5 (mg/kg/day)-1, which can be used to estimate the probability of excess risk for a lifetime of exposureto arsenic. Cancer risk was estimated based on the maximum concentration of arsenic in the contaminated surfacesoils at each of the locations. The cancer effect level (CEL) for arsenic in humans is 0.0011 mg/kg/day which isassociated with lung cancer.

No studies were found regarding populations unusually sensitive to arsenic. Since arsenic toxicity may be influencedby the rate and extent of methylation in the liver, some population might be especially susceptible because of lowermethylating capacity. This reduced capacity could result from dietary deficiency of methyl donors (choline ormethionine). Liver disease does not appear to decrease methylation capacity in humans for low levels of arsenic exposure.

Cadmium (ATSDR 1999b)

MRLs for acute and intermediate exposures have not been established. ATSDR has established a chronic oral MRL(0.0002 mg/kg/day) for cadmium. The NOAEL for humans is 0.0021 mg/kg/day. Doses exceeding this level areassociated with symptoms such as protein in the urine.

Cadmium is classified by EPA as a probable human carcinogen based on epidemiological studies of humans. Thesestudies indicate that cadmium may be a carcinogen when inhaled, with the resulting condition being lung cancer.These conditions occurred in occupational settings at concentrations which are generally higher than those found inthe outdoors environment.

Lead (ATSDR 1999c)

ATSDR has no MRL and EPA has no RfD for lead. Exposure to lead can cause a wide range of effects. The lack ofa clear threshold for health effects and the need to consider multi-media routes of exposure makes evaluating therisks from exposure to lead in the environment difficult. Blood lead concentrations are a good measure of recentexposure, and also correlate well with health effects. Children are especially sensitive to lead, and many of its effectsare observed at lower concentrations in children than in adults. Levels of 10 µg/dL, and perhaps lower in children'sblood, have been associated with decreased IQ, impaired hearing and growth, and neurobehavioral effects. Theneurological effects have been shown to persist after exposure has ceased and blood lead levels have returned tonormal.

Other reported neurological effects include poor memory, difficulty reading and concentrating, depression, and sleepdisturbances. Lead can significantly affect both the reproductive process and the development of the fetus in womenwith blood lead levels as low as 10 µg/dL. Effects include premature birth and low birth weight. In adults levels aslow as 15 µg/dL are linked to increased blood pressure, reduced production of sperm, earlier onset of menopause,and inhibition of enzymes responsible for the production of hemoglobin.

The increased vulnerability of children results from a combination of factors, including:

the increased susceptibility of developing nervous system to neurotoxic effects of lead,

a higher average rate of soil/dust ingestion among children,

the greater efficiency of lead absorption in the gastrointestinal tract of children,

a greater prevalence of iron or calcium deficiencies (can increase absorption of lead), and

the ready transfer of lead across the placenta to the developing fetus.

Foods such as fruits, grains, meat, seafood, soft drinks, vegetables and wine may contain lead. Cigarettes alsocontain small amounts of lead. More than 99% of all drinking water contains less than 0.005 milligrams of lead perliter. However the amount of lead taken into the body through drinking water can be higher in communities withacidic water supplies. Children residing in older dwellings may be exposed to lead by eating lead-based paint chipsfrom peeling surfaces. The normal wear of lead-based point surfaces such as that which might occur raising andlowering windows, can lead to the creation of lead dust which can also be ingested by small children during normalhand-to-mouth activities. Lead-based paint is particularly a problem in lower income communities. Foroccupationally exposed individuals the usual route of exposure is through the inhalation of lead particles.

Lead is classified by EPA as a Class B2 probable human carcinogen based on animal studies. This means that thereis inadequate evidence to determine lead's carcinogenicity in humans. The National Toxicology Program (NTP)classifies lead phosphate and lead acetate as Group 2 carcinogens (probable human carcinogens).

Studies regarding exposure to lead and possible adverse health effects are discussed more extensively in the publichealth implications section of this document.

Mercury (ATSDR 1999a)

ATSDR has developed a chronic oral MRL for methyl mercury (0.0003 mg/kg/day). The RfD for methyl mercury is0.0001 mg/kg/day. NOAEL for methyl mercury is 0.0013 mg/kg/day. The FDA has established an action level ofone mg/kg for methyl mercury in fish.

Methyl mercury is the form of mercury most easily absorbed through the gastrointestinal tract (about 95% absorbed).Exposure to methyl mercury can come from foods contaminated with mercury on the surface (for example, fromseed grain treated with methyl mercury to kill fungus) or from foods that contain toxic levels of methyl mercury (asin some fish, wild game, and marine mammals). Mothers who are exposed to methyl mercury and breast-feed theirinfant may also expose the child through the milk.

Critical periods of neonatal development and the early months after birth are times that are particularly sensitive tothe harmful effects of methyl mercury on the nervous system. Exposure to methyl mercury is more dangerous foryoung children than for adults because methyl mercury more easily passes into the developing brain of youngchildren and may interfere with the development process. Methyl mercury can accumulate in fetal blood toconcentrations higher than in the mother. Abnormal heart rhythms have been seen in children who ate grainscontaminated with very high levels of methyl mercury. Methyl mercury that enters the body can be converted toinorganic mercury and result in kidney damage.

Individuals with diseases of the liver, kidneys, lungs, and nerves are considered to be at a greater risk of sufferingfrom the toxic effects of organic mercury. Individuals with a dietary insufficiency of zinc, glutathione, antioxidants,or selenium or those who are malnourished may be more susceptible to the toxic effects of mercury poisoningbecause of the diminished ability of these substances to protect against mercury toxicity.

APPENDIX E: LIMITED FISH MEALS CALCULATED BY THE STATE OF IDAHO BASED ON BASS, BULLHEAD AND KOKANEE SAMPLES COLLECTED FROM LAKE COEUR D'ALENE IN 2002

Table 1.

Limited Fish Meals Per Month for Bass

Sample Type, Location

Chemical

Concentrations (mg/kg wet)

Meals Per Month*

Range

Arithmetic Mean

General (8 oz)

Pregnant Women (8 oz)

Children (4 oz)

GC (North)

Mercury

0.075-0.357

0.174

NA

5.4

3.1

Arsenic

0.034 (U)-0.215

0.126

13.3

11.6

6.6

Lead

0.01-0.467

0.156

185

40

25

Cadmium

0.006 (U)-0.044

0.0209

514

450

257

Zinc

12.686-24.227

17.4

185

162

93

Lowest Meals

13

5

3

GC (Center)

Mercury

0.108-0.341

0.171

NA

5.5

3.1

Arsenic

0.062 (U)-0.211

0.115

14.5

12.7

7.3

Lead

0.035-0.334

0.197

146

32

20

Cadmium

0.006 (U)-0.017

0.00765

1403

1228

702

Zinc

8.821-14.672

12.3

262

229

131

Lowest Meals

15

6

3

GC (South)

Mercury

0.0635-0.17

0.111

NA

8.5

4.8

Arsenic

0.073-0.235

0.146

11.4

10.0

5.7

Lead

0.011-0.153

0.0342

843

183

>26

Cadmium

0.012 (U)-0.067

0.0152

706

618

353

Zinc

10.663-19.302

13.5

238

209

119

Lowest Meals

11

9

5

FL (Center)

Mercury

0.121-0.386

0.188

NA

5.0

2.9

Arsenic

0.048 (U)-0.115

0.0639

26.1

22.9

13.1

Lead

0.009 (U)-0.047

0.0198

1456

316

>26

Cadmium

0.005 (U)-0.108

0.0151

711

622

356

Zinc

3.302-5.744

4.87

661

579

331

Lowest Meals

26

5

3

Meal Size: 8 oz for general population and women of childbearing age, 4 oz for children under seven

>26: more than 26 meals per month

NA: there is no methyl mercury RfD for general population to calculated the corresponding limited meals.

Table 2.

Limited Fish Meals Per Month for Bullhead

Sample Type, Location

Chemical

Concentrations (mg/kg wet)

Meals Per Month*

Range

Arithmetic Mean

General (8 oz)

Pregnant Women (8 oz)

Children (4 oz)

GC (North)

Mercury

0.0172-0.0512

0.0283

NA

33.2

19

Arsenic

0.048 (U)-0.099

0.0715

23.4

20.4

11.7

Lead

0.517-3.696

1.42

20.3

4.4

2.7

Cadmium

0.02-0.056

0.0342

314

275

157

Zinc

15.299-22.422

17.9

180

157

90

Lowest Meals

20

4

3

GC (Center)

Mercury

0.0246-0.0752

0.0451

NA

20.8

11.9

Arsenic

0.046 (U)-0.511

0.218

7.7

6.7

3.8

Lead

0.07-14.12

3.85

7.5

1.6

0

Cadmium

0.009-0.164

0.0771

139

122

70

Zinc

10.328-39.956

19.7

164

143

82

Lowest Meals

8

2

0

GC (South)

Mercury

0.0398-0.0708

0.0518

18.1

10.4

Arsenic

0.051 (U)-0.11

0.0503

33.2

29.1

16.6

Lead

0.038-1.353

0.479

60.2

13

8

Cadmium

0.01 (U)-0.056

0.0195

551

482

275

Zinc

12.738-19.907

14.8

218

190

109

Lowest Meals

33

13

8

FL (North)

Mercury

0.0263-0.052

0.0385

NA

24.4

13.9

Arsenic

0.046 (U)-0.049

0.0241

69

61

35

Lead

0.016-0.076

0.0288

1001

217

>26

Cadmium

0.009 (U)-0.015

0.00645

1665

1457

832

Zinc

4.792-6.215

5.52

584

511

292

Lowest Meals

69

24

14

FL (Center)

Mercury

0.0344-0.138

0.0646

NA

14.5

8.3

Arsenic

0.045 (U)-0.328

0.116

14.4

12.6

7.2

Lead

0.01-1.494

0.232

124

27

16.8

Cadmium

0.009 (U)-0.034

0.0161

667

584

333

Zinc

4.199-7.171

5.29

609

533

304

Lowest Meals

14

13

7

FL (South)

Mercury

0.0526-0.0721

0.0632

NA

14.9

8.5

Arsenic

0.048 (U)-0.052

0.0276

61

53

30

Lead

0.010-0.080

0.026

1109

241

>26

Cadmium

0.009(U)-0.011(U)

0.005

2147

1879

1073

Zinc

4.522-5.335

5.03

640

560

320

Lowest Meals

61

15

9

Meal Size: 8 oz for general population and women of childbearing age, 4 oz for children under seven

>26: more than 26 meals per month

NA: there is no methyl mercury RfD for general population to calculated the corresponding limited meals.

Table 3.

Limited Fish Meals Per Month for Kokanee

Sample Type, Location

Chemical

Concentrations (mg/kg wet)

Meals Per Month*

Range

Arithmetic Mean

General (8 oz)

Pregnant Women (8 oz)

Children (4 oz)

GC (Whole Lake)

Mercury

0.067-0.0853

0.0752

NA

12.5

7.1

Arsenic

0.105-0.194

0.145

11.5

10.1

5.8

Lead

0.061-0.2

0.115

251

54

>26

Cadmium

0.112-0.205

0.139

77

68

39

Zinc

17.292-27.361

20

161

141

81

Lowest Meals

12

10

6

FL (Whole Lake)

Mercury

0.0787-0.104

0.0917

NA

10.2

5.9

Arsenic

0.051-0.117

0.0831

20.1

17.6

10

Lead

0.011 (U)-0.046

0.0203

1420

308

>26

Cadmium

0.012 (U)-0.029

0.0177

607

531

303

Zinc

5.628-10.746

7.05

457

400

228

Lowest Meals

20

10

6

Meal Size: 8 oz for general population and women of childbearing age, 4 oz for children under seven

>26: more than 26 meals per month

NA: there is no methyl mercury RfD for general population to calculated the corresponding limited meals.

APPENDIX F:

JOINT FISH CONSUMPTION ADVISORY ISSUED BY THE STATE OF IDAHO AND THE COEUR D'ALENE TRIBE

Fish were collected from Lake Coeur d'Alene in May and August of 2002 as described in the Coeur d'Alene LakeFish Investigation Plan (USEPA 2002a), and were analyzed for metals (mercury, arsenic, lead, cadmium and zinc)to determine if the fish are safe for consumption by members of the general public and the Coeur d' Alene Tribe.Sampling locations in the Lake are shown in Figure 1. The results of the laboratory analysis of the fish samples areprovided in the Coeur d'Alene Lake Fish Investigation Data Report (USEPA 2003).

Based on extensive discussions among scientists and interested parties, kokanee (Oncorhynchus nerka), Bass(mostly largemouth bass, Micropterus salmoides), and bullhead (mostly brown bullhead, Ameirus nebulosus) wereselected as the target species because of their use by both tribal and sport/recreational fishers. All three species areextensively used by tribal subsistence fishers. Notably, the three species are also of ecological importance to theLake Coeur d'Alene fishery and encompass a variety of feeding habits and exposure patterns to contaminants.

Kokanee are primarily planktivorous, feeding on microscopic plants and animals in the water column, whereaslargemouth bass are predatory on other fish. Kokanee range throughout the Lake, whereas bass are lurking predatorswith a relatively small home range compared to kokanee. The large home range of kokanee means that they shouldserve as a good indicator of contaminant concentrations throughout Lake Coeur d'Alene. Largemouth bass, whichprey on other fish and have a smaller home range, should be more indicative of contaminant concentrations inlocalized areas of the Lake. Some smallmouth bass were also collected during the field effort. Bullheads are mostlybottom feeders and are normally closely associated with bottom sediments.

The tissue types analyzed were intended to be representative of two of the major methods by which fish caught inLake Coeur d'Alene are prepared for consumption by subsistence and sport/recreational fishers, i.e. gutted wholefish and fillets. The gutted whole fish tissue type consisted of remaining tissue after the removal of the caudal (tail)fin, gills, and guts with the exception of the kidney. The gutted whole fish carcass tissue sample was intended torepresent the most commonly used preparation method for fish that are smoked, canned, and that are used in soupsor stews. Fillets are commonly consumed by tribal, sport and recreational fishers.

Data collected indicate that mercury, lead and arsenic are the three contaminants with high enough concentrations infish tissue to warrant a fish advisory. Table 1 shows the species-specific, limited meal (the amounts of fish the IdahoFish Consumption Advisory Program [IFCAP] considers safe to consume) advisory. Where applicable, species-specific consumption rates are given for sections of the Lake as opposed to a blanket statement about the entireLake.

Table 1.

The Species-specific, Limited Meal Advisory

Species

Sample Type

Location

Consumption Advisory (meals per month)

Contaminant of Concern

General Population (8 oz. meal)

Pregnant Womena(8 oz. meal)

Childrenb(4 oz. meal)

Bass

Gutted Whole Fish

North

13

5

3

Arsenic: general population Mercury: pregnant women & children

Center

15

6

3

South

11

9

5

Fillet

Whole Lake

26

5

3

Bullheadc

Gutted Whole Fish

North

20

4

3

Lead

Center

8

2

0

South

33

13

8

Fillet

North

69

24

14

Arsenic: general population Mercury: pregnant women & children

Center

14

13

7

Arsenic

South

61

15

9

Arsenic: general population Mercury: pregnant women & children

Kokanee

Gutted Whole Fish

Whole Lake

12

10

6

Arsenic

Fillet

20

10

6

Arsenic: general population Mercury: pregnant women & children

a: Pregnant women, women planning to be pregnant, and nursing mothers.b: Children 6 years old or younger.c: People, especially children and pregnant women with increased blood lead levels, or living in an area with high concentrations of lead in the yard soil or house dust should eat less whole Bullhead than suggested in this advisory.

Due to the limited resources, only three representative fish species were sampled from Lake Coeur d'Alene as discussed above. Per Charles Corsi and Ned Horner (Idaho Department of Fish and Game), other fish species regularly caught in Lake Coeur d'Alene could be grouped according to behavior similarity to one of the three sampled species (bass, kokanee and bullhead) IFCAP currently has data for:

Although there are no fish tissue metal data for fish species other than bass, bullhead and kokanee, IFCAP believes the metal concentrations in the same group of fish species should be similar. Therefore, IFCAP suggests people compare the game fish they catch to the appropriate species group (bass, bullhead, and kokanee) and limit their consumption accordingly. For instance, IFCAP suggests that children limit their consumption of bluegill to 6 meals per month, the same as kokanee.

Other Basic Information

This fish advisory delineates how much and which type of fish can be safely consumed from Lake Coeur d'Alene, and which populations are most affected by the advisory. An issued fish advisory does not mean that people should stop eating fish from the Lake. In fact, metals found in fish from the Lake are lower than metals found in some fish purchased from the grocery such as shark, swordfish, and tuna. There is no need to substitute grocery store purchased fish for Lake-caught fish. By following the advisory, it is unlikely any ill effects will result from eating the fish caught from Lake Coeur d'Alene. This fish advisory is not mandatory and is issued only as a precaution in the interests of public health and safety.

In general, consuming smaller, younger fish (within Tribal and State legal limits) and those lower on the food chain is advised because these fish tend to be less contaminated. Also, insectivores and filter feeders may be preferable to bottom feeders since they do not contact sediment as much as bottom feeders.

Future Actions

Bass, bullhead and kokanee were sampled and analyzed for mercury, arsenic, lead, cadmium and zinc concentrations in the edible tissue. Mercury, lead and arsenic are the three contaminants with high enough concentrations in fish tissue to warrant a fish advisory.

Because the fish samples from Lake Coeur d'Alene fulfill the IFCAP sampling protocols (more than 10 fish per species per sampling location), a formal fish advisory has been issued. The governments involved in the Lake Coeur d'Alene fish study suggest sampling more fish in the future when possible, to verify whether or not they continue to pose a public health threat.

The Idaho Department of Health and Welfare laboratory will analyze the polychlorinated biphenyl (PCB) concentrations in all the fish tissue samples. When the data are available, the governments involved in the Lake Coeur d'Alene fish study will revisit this fish advisory if warranted by the PCB levels.